Tertiary phosphines and methods of preparing same



Uniter 3,116,316 TERTIARY PHOSPHINES AND METHODS OF PREPARING SAME Michael M. Rauhut, Nor-walk, Conn., assignor to American Cyanamid Company, New York, N.Y., a corporation of Maine No Drawing. Filed July 21, 1961, Ser. No. 125,640 3 Claims. (Cl. 260-465) The present invention relates to novel tertiary phosphines. More particularly, the instant discovery concerns monocarbamoyl-substituted tertiary phosphines.

According to the present invention, novel tertiary phosphines of the formula Reaction is best carried out in the presence of an inert organic solvent, such as an aromatic hydrocarbon, an ether, a halogenated hydrocarbon, or the like. Typical inert organic solvents are xylene, benzene, toluene, tetrahydrofuran, dioxane, chlorbenzene, chloroform, and the like.

Reaction may be made to take place at super-atmospheric, atmospheric, or sub-atmospheric pressure, preferably at atmospheric pressure. The sequence of addition is not critical, and the reaction may be performed under 3,115,315 Patented Dec. 31, 1963 range of temperatures may be employed, excellent results being achieved at ambient temperature. While temperatures in the range of 30 C. to 110 C. are preferred, temperatures as low as C. and as high as 200 C. may be used.

Typical isocyanate reactants contemplated herein are aryl isocyanates, such as phenyl isocyanate, para-chlorophenyl isocyanate, 2,5-dichlorophenyl isocyanate, para nitrophenyl isocyanate, meta-tolyl isocyanate, ortho-chlorophenyl isocyanate, para-methoxyphenyl isocyanate, meta-nitrophenyl isocyanate, l-naphthyl isocyanate, 2- naphthyl isocyanate, and the like. It can be seen that typical inert substituents for the aryl isocyanates contemplated herein are lower alkyl, nitro, lower alkoxy, halogen (e.g. chlorine, bromine, etc.), and the like.

If desired, organic basic catalysts, including pentamethylguanidine, tertiary amines, such as tri-alkyl (C C amines may be employed to enhance the reaction con templated herein. Only small amounts of these catalysts need be employed, i.e., amounts up to about 10 percent by weight based on the total Weight of the ractants. As little as 0.05 percent by weight or less will often be helpful.

The present invention Will be illustrated hereinafter by examples which are intended to further describe, not limit, the scope of the invention.

EXAMPLE I p-Chloropheny lcarbamy Ibis (Z-Cyanoethyl) Phosp/zine A solution of 5.0 grams (0.036 mole) of bis(2-cyanoethyl)phosphine and 6.0 grams (0.039 mole) of p-chlorophenylisocyanate in milliliters of benzene is heated to reflux under a nitrogen atmosphere. Heating is discontinued and 5 drops of triethylamine is added. When the mild reaction subsides, heat is again applied and the solution is refluxed for one hour. The reaction mixture is filtered while hot, and the filtrate when cool is diluted with petroleum ether. The oil which separates is combined with a small quantity of benzene, and crystallization is induced by scratching. After recrystallization from acetone-petroleum ether the melting point is 125 C.

EXAMPLES II-VllI The following tabulated examples are carried out essentially as in Example I, above, the essential reaction conbatch, continuous or semi-batch conditions. A wide dition differences being speclfied 1n the table:

TABLE I ll R R PH RNCO R1R2PC-NR Reaetants Ratio Tem- Product Example Catalyst Phosphine: pera- Solvent Isoeyanate turn, Phosphine Isocyanate 0. R R; R

II diethy1phos para-ehl0r0- tributyl- 1:1 xylene ethyl ethyl para-chlorophine. phenyl isoamine. phenyl.

eyanate. III dioetylphos- 2,5-dichl0rotrimethyl- 1:1 20 tetrahydroiuran octyl octyl 2,5-dichlorophine. phenyl isoamine. phenyl.

cyanate. IV didodecylpara-nitrotributyl- 3:1 90 dioxane dodeeyl dodeey1 para-nitrophosphine. phenyl isoamine. phenyl.

cyanate. V diisopropylmeta-tolyl tripropyl- 1:1 30 toluene isopropy1 1sopropy1 meta-tolyl.

phosphine. isocyanate. amine. VI dicyclohexylpararnethtriethyl- 1:3 dimethylformamidc--. cyclohexyln cyol0hexyl para-methphosphine. oxyphenyl amine. oxyphenyl.

isocyanate. VII dieyclopentyll-naphthylpentamethyl- 1:1 22 chloroform eyelopentyl. eyclopentyll-naphthyl.

phosphiue. isocyanate. guanidine. VIII dioctadecylpara-bromodo 1:2 50 trichloroethane 0ctadeey1 oetadeeylnn para-bromophosphine. phenyl isophenyl.

eyanate.

H IIVII IIVVIII 3 EXAMPLE IX Dibutyl(1-Naplztlzylcarbam0yl)P/zosplzine EXAMPLES X-XXIII The following tabulated reactions are carried out essentially as in Example IX, above, the essential differences in reaction conditions being specified in the table:

modifications within the skill of the art. Consequently, while the present invention has been described in detail with respect to specific embodiments thereof, it is not intended that these details be construed as limitations upon the scope of the invention, except insofar as they appear in the appended claims.

I claim:

1. A tertiary phosphine of the formula I R1R2P(H]NR wherein R is a member selected from the group consisting of phenyl, naphthyl and substituted phenyl, said substituents for phenyl being selected from the group consisting of lower alkyl, nitro, lower alkoxy and halogen; R and R each represent a member selected from the group consisting of alkyl having from 1 to 18 carbon atoms, substituted alkyl having from 1 to 18 carbon atoms, cyclohexyl, cyclopentyl, phenyl, substituted phenyl,

TABLE II II I RlRflIPI'I BN0 0 R1R PC-N-R Reaetants Ratio Tem- Product Example Catalyst lhosphine: pera- Solvent Isoeyanale ture, Phosphine Isocyanate 0. R1 R; R

dimethylphenylisonone 1:1 benzene methyl methyl phenyl,

plresphlne. cyanate. (lloctylpllosnleta-ehlorodo 11 6 diethylether octyl oetyl. meta phine. phenyl isochloroeyanate. phenyl. didodeeylpara-n1ethyl- 1rietl1yl- 3:1 100 toluene dodeeylun dodeeyl..-.- para-methylphosphine, phenyl isoamine. phenyl.

eyanate.

XIII dilsobutylpara-fiuoro none 1:1 chloroform isobutylnm isobuty1 pal'flphosplnne. phenyl isofluoroeyanate. phenyl.

XIV dietllylphosmeta(trid0 1:1 35 CH OCHZCHZOCH3.. ethyl ethyl meta(tri-.

phine. fluoromethyl)- phenyl isocyanate.

XV bls(tri[luoro- Z-naphthyl lo 1:1.5 7() benze e tr1- tn- 2-napl1tl1y],

methyD- isoeyauate. Iluorofluorophosphine. methyl. methyl.

XVI diphenylphosmeta-brornotiiethyl- 11 82 do phenyl phenyl metaplnne. phenyl isoamine bromoeyanate. phenyl.

XVI1 dibenzylphosphenyl 1:1 85 .-..d0 benzyl benzyl phenyl.

phine. isoeyanate.

XVIII bis(2-butoxypara-methyl tributyl- 1.512 95 toluene 2-but0xy- Z-butoxyparaethyl)- phenyl isoamine. ethyl. ethyl. methylphosphiue cyanate. phenyl.

XIX bis(para phenyl tripropyl- 1:1 chloroform para-chloropara-chlorophenyl,

ehloroisoeyanate. amine. phenyl. phenyl. phenyl)- phosphine.

XX bis(parado triethyl- 4:1 benzene parapara- Do. methylamine. methylmethylphenyl)- phenyl. phenyl. phosphine.

It follows from the above representative examples that typical substituents for the secondary phosphine reactants are lower alkyl, phenyl, halogen, lower alkoxy, cyano, and the like. characteristically, these and like substituents are inert under the reactions contemplated herein.

The products of the present invention are useful as fire retardants for cotton cloth, as indicated hereinabove. For example, cotton cloth dipped, according to well-known procedures, in a suitable solution of any one of these monocarbamoyl s fibs'tituted tertiary phosphines manifests desirable fire retardance.

Clearly, the instant discovery encompasses numerous naphthyl and substituted naphthyl, said substituents for alkyl being selected from the group consisting of halogen, lower alkoxy, cyano and phenyl, and said substituents for phenyl and naphthyl being selected from the group consisting of lower alkyl, halogen, lower alkoxy and cyano.

2. Para-chlorophenylcarbamylbis(2 cyanoethyl)phosphine.

3. Dibuty1(l-naphthylcarbamoyl)phosphine.

References Cited in the file of this patent UNITED STATES PATENTS 2,969,390 Buckler Jan. 24, 1961 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 3 ll6 3l6 December 31 1963 Michael M, Rauhut It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Columns 1 and 2 for "1:1" read 1:2 mole columns 3 thereof for "6" read TABLE I fifth column line 2 thereof column 3 line 6 for "mode" read and 4 TABLE I1 sixth column line 2 W 60 Signed and sealed this 30th day of June 1964;

(SEAL) Attest:

ERNEST W; SWIDER A! blasting Officer EDWARD J. BRENNER Commissioner of Patents 

1. A TERTIARY PHOSPHINE OF THE FORMULA 